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Pics of your rig's MOUNTING HARDWARE

I was going to ask one of the pic-posters to show some close-ups of their mounting hardware (sub-frames, struts, dampers, brake pedals, etc.) in the Pics of your Rig forum but decided it would "muddy up" the thread.

So... .

If you have any close up shots of the various components on your rig would you post them here.... just no cup-holders, okay?

"It is what you discover, after you know it all, that counts." _ John WoodenLew Morris
1973 R75/5 - original owner
1963 Dnepr

Here's a shot of the connectors on my R100/Ural rig. First, note that I've added a new receiver on the sidecar frame to accept a "rear" jaw clamp in the appropriate position for a /7 frame. What you can't see is a cross brace from inside the passenger peg bracket to the left side of the frame.

If you look closely, you can see a parallel brake pedal. That's the sidecar brake, and having a parallel lever keeps the sidecar brake system separate from the bike, and also allows easy detachment of the sidecar.

Notice the added upper rear strut. That's just extra bracing for offroad use. And if you look closely, you can see another cross brace under the cylinder, between the sidecar front receiver and the rear engine bolt. So, 6 cross braces in total.

I elected to use the stock Ural jaw clamps, but the lower front connector has been modified. It's a "rear" J clamp inserted in a new receiver, welded with two inches extra width to help clear the BMW cylinder head.

Here's a shot of my leading link front end, which started out in life as a Heddingham "Unit" fork. I reinforced the two leading links with gussets at the rear, and added some vertical bracketry to allow repositioning the link in either solo or sidecar trail.

The fender is an extensively modified front "rain" fender, widened to accept a 4:00 x 18 knobby. It's mounted to the cross brace I added between the upper shock clamps on the downtubes. The cross brace helps make the downtubes more rigid, but also makes a handy place to support the high fender. The front of the fender is held up by a Ural front fender brace and some home-brew ss brackets. The fender snugs right up under the mini-fairing.

I used the ATE brakes, although in retrospect I should have sprung for Brembos. The ATEs hang horizontal, and capture mud and water. Brembos could have been supported horizontal on floating carriers, and being mounted on top of the discs would stay cleaner and allow "neutral dive" braking.

The upper brake hoses are ss braided, and the lower brake "pipes" (tubes) are steel, but armored with rubber hose to help stave off rocks. Shock absorbers are Koni.

The front wheel in this picture is a 19" Lester with a square profile sidecar tire. I also have an 18" offroad wheel, with Sun alloy rim laced to a reinforced hub with heavy gage ss spokes. Likewise the "offroad" rear wheel.

Could we see a shot perpendicular to the center-line of the bike (from the right side of the chair)? Please...

What type of "frame" clamps work best on the tapered down-tubes found on old /5-6s? I'm guessing a sub-frame instead....

Thanks, Lew

edit- forgot to mention that yesterday I got to look at an older GL1000 rigged up to a Watsoninan (which model I'm not sure). We were at a truck stop on 101 so I didn't get to nose around for too long. The owner did the installation himself and used double "U"bolts and backing plates - i.e. two "U" bolts on either side of a frame tube - it didn't look too secure to me and it seems like there would be a lot of point-pressure under those bolts. Comments please.

"It is what you discover, after you know it all, that counts." _ John WoodenLew Morris
1973 R75/5 - original owner
1963 Dnepr

I call them "shock pants". Home sewn out of cordura or something like that. They just slip over the top of the shock with the bolt removed. Keeps out the big debris.

I didn't use a subframe. Rather, I depend on the main frame, but reinforce it with various bits and pieces to control bending/torquiing. The lower front main strut clamps to a ball screwed on the end of the engine bolt, but I reinforced the ball with a short bar brazed on, secured with ss straps around the frame to keep the engine mounting bolt from bending.

The upper front mount is another custom job. The R100 frames have two cross tubes, where the R75 frame has a single cross tube. On my R100 I welded up a shaped split clamp that secures around the upper curved cross tube. Since it's formed in a curved shape, once it's bolted up it can't budge. The attachment is through a large aircraft style eye bolt. If I were installing on an R75, I would make up a strut that clamps around both frame tubes.

The lower rear attachment is to another ball bolted through the passenger peg bracket. On the inside, there is barely room to squeeze a tube through the brake mechanism to attach to the left side of the frame. That's because the thin passenger peg bracket is not very resistant to side loads.

The upper rear strut attaches to a custom eye bracket that bolts through the frame/subframe connection with a high strength 3/8" bolt. And I also use a cross tube to brace the sides of the frame. The threaded tube inserts between the two lower holes in the subframe bracket, using tapered clutch bolts to take care of the unsquare alignment.

U-bolts are a bit too crude for me to use as sidecar fittings. They don't spread the load across the frame tubing, and it doesn't take much crushing or dimpling of a frame to cause it to fail. There are strap clamps that are a step above an industrial U-bolt, but strap clamps all have the disadvantage of slipping under use. My preference would be for a split clamp using several connector bolts.

At the moment, I'm a bit limited by a "bad" leg, but I'll try to shoot some additional details when I get mobile again.

There really isn't any "standard" sidecar attachment hardware. Each conversion usually requires the fabrication of clamps to fit the bike or sidecar. So, if you need a clamp like this, just make up a drawing and take it to a welding shop. It's not hard to fabricate once you know the shape and dimensions. Clamps like this can be made of mild steel, and held together with high strength (grade 8) bolts.

I've retouched thie photo to give you a better idea of the shape. If this were to go around an oval frame tube, just give the welder the dimensions. The mild steel will deform slightly to grip the frame.

I got a good look at a Cozy Sport Max Standard this week; I was taking in all the mounting details so I could apply them to this Bingham project I have.

I have all the major struts for this old chair, but the tangs (Cozy's definition) are old and pitted. I couldn't care less about the surface finish (powder-coat is a wonderful restorer) but I am more than a little concerned about the underlying metallurgy. These parts are 41 years old and I have issues with the "square" cut corners (where the head meets the shank) that lead to stress cracks.

The Bingham "tangs" are 1/2" diameter (Cozy's are 18mm [.71"]) and fit through tubes brazed into the frame. I think 1/2" is a bit light for the duty I had in mind, but there is no way to step up to the larger "Cozy" sized parts, short of drilling out and fitting new tubes in the frame (which is more effort than I care to expend). A new frame would be easier to build. So, at this point I think I'll just restore this old rig and sell it to someone interested in a town-hack; it would be perfect on a 450+.

Copyright Sport Max Sidecars

Is anyone else offering mounting components for sale besides cozy? I see plenty of sidecars but not much in the way of "hardware".

Barring that I suppose it's McMaster-Carr time.

"It is what you discover, after you know it all, that counts." _ John WoodenLew Morris
1973 R75/5 - original owner
1963 Dnepr

Yep, sidecar mounting hardware is specialty stuff, and not available at your local hardware or farm equipment store. It's a small enough industry that just about everything is custom made.

If you're cheap and resourceful, fabricate your own. Saw out pieces of steel with your metal cutting bandsaw, and have a good welder put them together. For ideas, see the "Yellow Book", Driving A Sidecar Outfit, 2nd edition.

Or, talk to one of the sidecar installers, such as Jay Giese at Dauntless Motors near Seattle. Jay makes up lots of different sidecar connectors, and can provide just about anything you need. I don't know if they have a catalog.

If you have an IMZ-Ural dealer in the vicinity, stop by for a chat. Sometimes they carry extra bits and pieces, or can order through the importer. In general, I have found Ural hardware to be sturdy and reliable. Other sidecar brands, including Cozy, Velorex, Jawa, etc. have lightweight hardware barely suitable for 350cc size machines.

[QUOTE=Lmo1131;590989]Thanks Dave, am I seeing sub-frame in the first shot?

Could we see a shot perpendicular to the center-line of the bike (from the right side of the chair)? Please...

I snapped a couple of shots of my R100 mounts. I left the dirt on so it would look "natural."

The first photo is of the lower front mount, which uses a ball on the engine stud reinforced with a horizontal bar--to allow ss straps around the main frame to help prevent the ball from bending the end of the engine stud, and to provide some redundancy. The "spare" ss clamp on the frame is for attaching a bash plate.

The black diagonal strut is to add some lateral support, and to add some rock armor under the exposed brake assembly. That square tube on the lower front sidecar strut is a jackstand receiver to support the sidecar when it is removed.

The upper rear strut attaches to an eyebolt through the frame/subframe fittings. And, to add some needed lateral bracing between the main frame rear loops, I have added a heavy wall ss tube held in place by clutch bolts through the lower holes in the frame bracket.

Last winter I decided to add an air prefilter, to help keep dust out of the airbox on unpaved roads. I made a fiberglass copy of the top of the air filter box, with an inlet at the upper rear. That's the big hole. The prefilter box spreads out to bridge over the cross tube.

The passenger peg is strong enough vertically to support a sidecar, but it's not very resistant to side loads.

I've added a diagonal brace between the ball mount on the passenger peg and the other side of the frame cross tube. It crosses below the swing arm, and attaches with a heavy ss clamp. The brake bracket had to be reworked slightly to allow room for the crossbrace attachment.

This is a critical part of the conversion, to allow this rig to fly through the air and land without coming apart.